DE69830052T2 - REPLACEMENT FOR REINFORCED BONE TRANSPLANT - Google Patents

Abstract

One embodiment of a spinal spacer 10 includes a body 11 sized and configured for engagement between adjacent vertebrae V. The body 11 includes two opposite faces 12, 14 and an outer surface 13 between the two faces 12, 14. In one embodiment, the body 11 includes deactivated bone material in synergistic combination with a bone growth factor. A sleeve 15 is disposed around the outer surface 13 of the body 11. The sleeve 15 is composed of a second material which is relatively stronger under compressive loads than the biocompatible material of the body 11. Also provided is a plurality of apertures 16 through the sleeve 15 in communication with the outer surface 13 of the body 11 for bone ingrowth. Means for attaching the sleeve to the endplates of adjoining vertebral bodies are also provided.

Description

The The present invention relates generally to stabilizing the spine. in the In particular, the invention relates to a replacement for reinforced bone graft.

BACKGROUND THE INVENTION

Intervertebral discs, which are located between the end plates of adjacent vertebrae, stabilize the spine, distribute forces between vertebrae and upholster vertebrae. A normal intervertebral disc includes a semi-gelatinous component, the nucleus pulposus, a from an outer fibrous one Ring, called annulus fibrosus, surrounded and enclosed. In a healthy, undamaged spinal column The annulus fibrosus prevents the nucleus pulposus outside of the disc space protrudes.

Band washers can postponed due to injury, illness or aging or damaged become. An interruption of the annulus fibrosus allows that the Nucleus pulposus protrudes into the spinal canal, a condition that commonly referred to as disk herniation or prolapse. The pushed out nucleus pulposus may press on the spinal nerve, causing nerve damage, pain, Deafness, muscle weakness and paralysis to lead can. Intervertebral discs can also degenerate due to the normal aging process or illness. If an intervertebral disc loses water and hardens, the Disc space height decreases, causing instability The spine, reduced mobility and pain leads.

Sometimes The only relief of the symptoms of these ailments is a nucleotomy or surgical removal of a section or the entirety of a Intervertebral disc followed by fusion of adjacent vertebrae. Removing the damaged or diseased disc will allow the disc space to collapse. One Collapse of the disc space may be in addition to severe pain, instability The spine, abnormal joint mechanics, premature development of arthritis or nerve damage cause. Often, prosthetic implants are used, a collapse to prevent the room. The implant must ensure a temporary support and allow the ingrowth of bone. The success of the nucleotomy and fusion process requires the Development of a subsequent Bone growth to produce a solid mass because of it can that be Do not implant the pressure loads on the spine for the life of the patient resists.

Lots Try the disc space after removing the disc To stabilize, have relied on metal devices. The US patent No. 4 878 915 to Brantigan teaches a massive metal plug. U.S. Patent Nos. 5,044,104, 5,026,373 and 4,961,740 to Ray, 5 015,247 to Michelson and U.S. Patent No. 4,820,305 to Harms et al. teach hollow metal cage structures. With the use of these metal implants are several disadvantages connected. Solid metal implants do not allow ingrowth of Bones, what the possible Failure of the implant may result. Surface porosity corrected This problem with such massive implants not because they insufficient ingrowth allows for a solid bone mass strong enough to withstand the stresses of the spine. On the other hand allow the hollow cage structures of Harms, Ray and Michelson a waxing. These devices can also filled with bone graft material to help bone growth to promote. Unfortunately Many of these devices are difficult to machine and to machine therefore expensive. About that can out Metal implants shield the bone graft against stress, which increases the time required for a merger to occur.

The Michelson implant also requires a special tool and a additional Dissecting the adjacent vertebral body, to secure a merger. A special press is needed to a compressed one Force core of osteogenic material into the device by force. The Osteogenic material taken from the iliac crest of the patient is, must be compressed, so that the material through openings in the implant expands, causing the graft material immediately touching the bone of the adjacent vertebrae. Michelson also requires To core a region of each adjacent vertebral body to a enough contact surface between the implant and the cortex to ensure the vertebrae.

The use of bone graft materials in these prior metal cage fusion devices has several disadvantages. Autograft, bone material surgically removed from the patient, are undesirable because they may not yield a sufficient amount of graft material. In addition, the additional autograft surgery removes the risk of infection and may reduce structural integrity at the donor site. The supply of allograft material obtained from donors of the same species is unlimited. However, allograft grafts are also disadvantageous due to the risk of disease transmission and immune responses. In addition, al lone bone does not have the osteogenic potential of autogenous bone and will therefore only provide temporary support.

On Have a need for safer bone graft materials in the most recent Time bone graft substitutes, such as bioceramics, considerable Attention found. Calcium phosphate ceramics are biocompatible and do not bring the infectious or immunological concerns of allograft materials with himself. Ceramics can be prepared in any amount, which is a great advantage over autogenous Bone graft material is. In addition, bioceramics are osteoconductive and stimulate bone formation at bone sites. Bioceramics make a porous Matrix ready, which further supports the growth of new bone. Unfortunately ceramic implants are typically lacking in strength high spinal loads and therefore require separate fixation the merger. An attempt to reduce the poor compressive strength of bioceramics to overcome, will be published in the International Publication No. WO 96/40014. The publication discloses a Implant a body with an outer surface and a height that nearly the height corresponds to a human disc space, and one with the Outside surface of the body engaged sleeve comprises the sleeve contains a material, that relatively stronger is under compression than the body.

From The calcium phosphate ceramics are most commonly hydroxyapatite and Tricalcium phosphate ceramics for a bone graft has been used. Hydroxylapatite is similar to inorganic bone substance and biocompatible with bone. However, it is slowly degraded. β-tricalcium phosphate is rapidly degraded in vivo and is too weak to be cyclic Strains of the spine to support, until the merger takes place. These ceramics have proved to be inadequate for providing temporary support after a nucleotomy proved while the merger is awaited.

It There is still a need for fusion spacers which stimulate bone ingrowth and avoid the disadvantages of metal implants but ensure sufficient strength to support the spine until the neighboring vertebrae are fused.

It there is still a need for bone graft substitutes, the osteogenic potential and the low risk of infectious or immunological complications of an autograft without the Ensure disadvantages of autograft.

SUMMARY OF THE INVENTION

To the present invention provides an interbody fusion spacer, that one body with an outer surface and a height, the approximate the height corresponds to a human disc space, and one with the Outside surface of the body engaged sleeve comprises the sleeve contains a material that relatively stronger under compression is called the body, characterized in that the Body out a deactivated bone material, including collagen or gelatin and of course associated Bone minerals, and that the deactivated bone material is substantially free of non-collagenous proteins.

To The invention is a spine spacer for engagement provided between vertebrae. The spacer includes a body sized for it and is configured to fill the space between the vertebrae, and two opposite ones surfaces and an outer surface between the two surfaces Has. The body includes a porous one biocompatible Material to allow the ingrowth of bone through it. The Material closes a deactivated bone material. A sleeve is placed around the outer surface of the body. The sleeve consists of a second material that is relatively stiffer than the biocompatible material of the body. The invention contemplates also an interbody fusion spacer with a Height, the nearly the height corresponds to a human disc space. With another specific embodiment a vertebral replacement spacer is provided, to restore the space by removing a damaged one spinal Elements is left, which is located between adjacent healthy vertebral bodies.

at a specific embodiment the invention provides a plurality of openings through the sleeve, in conjunction with the outer surface of the body for ingrowth of bones. In another embodiment becomes the sleeve made of a temperature-responsive material, So that the Chamber when the sleeve in a heated state, has a first inner dimension, the slight is larger as an outer dimension of the body, around the body sliding into it. The chamber has, when the Sleeve in a cooled Condition is a second inner dimension, which is slightly smaller is as the body, thereby the body in to clamp it.

In another specific execution According to the invention, a fastening means is provided for attaching the sleeve to the end plates of the adjacent vertebral bodies.

It It is an object of the invention to provide a spacer for engagement between vertebrae which promotes bone ingrowth and avoids stress shielding. It is another task the invention, a spacer to provide the intervertebral disc space and the spine supports while it is promotes bone ingrowth. It is another object to use a vertebral replacement spacer for use When restoring the space by removing a damaged one spinal Elements is left while a Fusion between the adjacent healthy vertebral bodies is promoted, provide.

In In one aspect, the invention provides a deactivated bone graft in synergy with a bone growth factor and enhanced with a sleeve ready. This embodiment is beneficial because it enhances the natural mineral structure of Bones with the osteoinductive potential of a bone growth protein connects in a load-bearing spacer.

It is an advantage of the spacers the present invention that they the advantages of porous, biocompatible Materials, such as deactivated bone products, with the advantages of metals, without the disadvantages of each material. An additional one The advantage is that the Invention a stable framework for the Ingrowth of bone before fusion occurs. Other Tasks and other benefits The present invention will be understood to those of ordinary skill in the art in the field obviously from the following written description and the attached Illustrations.

SHORT DESCRIPTION THE DRAWINGS

1 Figure 10 is a side view of a spinal implant according to one embodiment of this invention.

2 is an exploded view of the implant of 1 ,

3 Figure 11 is a partial side sectional view of a spine with an implanted cylindrical interbody fusion device.

4 is a partial side sectional view of a spine with an implanted cylindrical vertebral body replacement device.

5 to 13 are alternative embodiments of the implant of 1 ,

DESCRIPTION THE PREFERRED EMBODIMENTS

To the Purpose of the promotion of an understanding the principles of the invention will now be referred to in The drawings illustrated embodiments, and there will be a specific language used to describe the same. Nevertheless It goes without saying that with it no restriction the scope of the invention is intended to reflect the changes and further modifications to the spacers shown and the further applications of the principles of the invention as herein is to include the professionals the field to which the invention relates normally should be.

The The present invention provides spinal implants that a body include, the from a porous one biocompatible Material is reinforced by a sleeve, which consists of a second Material that is relatively stiffer under the pressure load of the spine is as the biocompatible Material is produced. The implants according to the invention restore the intervertebral space, set one larger surface to Ingrowth of bones ready and eliminate the need for Autogentransplantaten. Ensure implants according to this invention immediate load capacity and prop for the spine, without shielding the bone graft material from stress. In some aspects, the body consists of a deactivated one Bone material in synergy with a bone growth factor, such as a bone morphogenesis protein (BMP).

A spinal implant 10 for an engagement between the vertebrae according to a preferred embodiment of the present invention is in 1 and 2 displayed. The spacer 10 closes a body 11 one made of a porous biocompatible material to allow tissue ingrowth therethrough. The body 11 closes two opposite surfaces 12 . 14 and one between the two surfaces 12 . 14 arranged outer surface 13 one. The body 11 will, as in 3 and 4 shown to be sized and configured for engagement between two vertebrae V.

3 shows an interbody fusion device 20 according to this invention engaged within the intervertebral space IS between two vertebrae V. Preferably, the body has 25 a height approximately equal to the height of a human disc space IS, and the opposite surfaces 26 . 27 of the body each have a size and shape corresponding to the end plates of each of the vertebrae V. As in 5 shown, the device can 40 a body 41 having a kidney-shaped cross-section approximately corresponding to the size and shape of a nucleus pulposus removed from an intervertebral disc, or the complete disc or vertebral end plate, and a correspondingly shaped sleeve 45 lock in. At the in 3 In the embodiment shown, the body is preferably sized and shaped so that it fits snugly into the space IS defined by the end plate and the annuli of the adjacent vertebral bodies V. An alternative form for the body will be in 6 and 7 shown. In some applications, it may be preferable that the height of the body 25 is slightly larger than the height of a human disc space IS to maintain the disc space height under the pressure loads of the spine and to avoid the effects of bone erosion.

The invention also contemplates, as in 4 shown vertebral body replacement devices 30 for use in restoring the space left by the removal of a defective spinal element located between adjacent healthy vertebral bodies V. In such cases, the body becomes 35 configured to be disposed within the space between adjacent vertebral bodies V. The invention contemplates that the body 35 may have any shape or size desirable for a spinal implant for engagement between vertebrae V.

Of the body consists of a porous biocompatible deactivated bone material to prevent bone ingrowth promote.

The porosity of the biocompatible Material is required for ingrowth, but it is generally understood that the strength decreases when the porosity increases. Implants according to the present invention will require porosity with strength requirements optimize to avoid breakage. The biocompatible Materials of this invention preferably include porosities of between about 40% and about 60%, with a porosity of 50% most preferable. For Bone ingrowth is a pore diameter of at least 200 to 600 microns required. Therefore, it is considered that the ceramics of the present invention has an average pore size of about 200 to about 700 Have micrometers. Preferably, the average pore size is about 400 microns.

Referring again to 1 and 2 includes a spinal implant 10 according to this invention, a around the outer surface 13 of the body 11 arranged sleeve 15 one. The sleeve 15 consists of a second material that is relatively stronger under pressure than the porous biocompatible material. Preferably, the second material is made of a metallic material. The metallic material includes any surgically suitable metal including titanium, titanium-vanadium-aluminum alloy, cobalt-chromium alloy, cobalt-chromium-molybdenum alloy, cobalt-nickel-chromium-molybdenum alloy, biocompatible stainless steel, tantalum , Niobium, hafnium, tungsten and alloys thereof. Preferably, the metal is a 316L stainless steel, titanium or tantalum foam. Most preferably, the metallic material is an open-cell tantalum foam, as described in U.S. Pat. No. 5,282,861 to Kaplan. This material is a carbon metal composite that includes a glass-carbon skeleton that defines a network of interconnected pores that are infiltrated by chemical vapor deposition with tantalum or other suitable metal. This material is advantageous because it provides the strength of other metals to serve as a framework and denture, but also mimics the bone structure. The interconnected pores of the foam serve as another site for bone ingrowth. According to the present invention, a tantalum disc can be prepared according to the Kaplan patent. The center of the tantalum foam sheet can be drilled out to obtain a metal foam sleeve. The implant 50 , this in 12 can be imaged from the metal foam sleeve 51 and a suitable body 52 getting produced.

With reference to 2 closes the sleeve 15 an inner surface 17 for touching the outer surface 13 of the body 11 one. The inner surface 17 the sleeve 15 defines a chamber 18 , The sleeve 15 is preferably made of a temperature responsive material so that the chamber 18 when the sleeve 15 is in a heated state, has a first inner dimension which is slightly larger than an outer dimension of the body 11 , In this state, the sleeve can 15 the body 11 sliding in the same record. The chamber 18 has, if the sleeve 15 is in a cooled state, a second inner dimension that is slightly smaller than the body 11 in order thereby to the body 11 to be clamped in the same. In other words, the sleeve 15 can be extended by the application of heat and then by cooling around the body 11 shrunk. Alternatively, the body can 11 if he is a ceramic, inside the chamber 18 the sleeve 15 be formed.

The size and shape of the sleeve 15 correspond as in 2 and 5 to 11 shown the configuration of the outer surface 13 of the body 11 , For example, if the body is cylindrical, the sleeve is as in 6 to 11 shown a hollow cylinder. In a specific embodiment of the invention, the sleeve has 15 a height that is less than a height of the outside surface 13 of the body 11 is to contact the opposite surfaces 12 . 14 of the body 11 with endplates of the corresponding vertebrae V, when the implant is implanted between vertebrae V.

With reference to 1 For example, an implant according to the present invention preferably includes a sleeve 15 one that has a variety of openings for bone ingrowth 16 defined by the same in conjunction with the outer surface 13 of the body 11 To be defined. Any suitable shape is contemplated for the openings. As in 6 to 11 As shown, the openings may be generally circular, oval, diamond or rectangular. However, the size and number of openings must be adjusted to the overall strength of the sleeve 15 maintain.

Preferably, the implants of the present invention include, as in 3 and 4 shown fastening means for securing the sleeve 21 . 31 the implants to the adjacent vertebrae V a. At a specific, in 3 In the illustrated embodiment, the attachment means closes at the top 26 and the lower end 27 the sleeve 21 arranged teeth 23 one. As in 4 Alternatively, the fastener may be shown at the top 36 and the lower end 37 the sleeve 31 defined roughened surfaces 33 . 34 lock in. The roughened surfaces can be formed by conventional machining techniques, such as knurling.

At an in 13 embodiment shown closes the sleeve 56 attacks 57 . 58 which contact the adjacent vertebral bodies to prevent the device 55 slips forward within the disc space.

In a preferred embodiment, the body becomes 11 of the spacer 10 formed from bone. The connection of the reinforcement sleeve 15 and the body made of a deactivated bone material 11 ensures a load-bearing bone graft. It is contemplated that any suitable bone material may be used. The bone material may be autogenous, allogenic or xenogenic. For example, the bone grafts of co-pending application USSN 08 / 740,031, filed October 23, 1996 (corresponding to WO 98/17209, filed October 21, 1997) can be connected to the reinforcing sheath of the present invention to provide a reinforced bone graft. which has a high compressive strength.

To of the invention, the bone material is deactivated, i.e. treated, to fat and protein too remove. The deactivated bone material may be, for example as in U.S. Patent No. 5,417,975 to Lussi et al., U.S. Patent No. 4,314,380 to Miyata et al., U.S. Patent No. 5,573,771 to Geistlich et al., U.S. Patent No. 4,882,149 to Spector, "A Chemosterilized Antigen-Extracted Autodigested Alloimplant for Bone Banks ", by Urist, MD, et al., In Arch Surg / Bd. 110, April 1975 and "Xenogenic Bone Grafting in Humans ", by Salama, in Xenogenic Bone Grafting, Number 174, April 1983, described. In some of these methods, this is deactivated bone material edited to remove all bone proteins, resulting in a powdery one mineral material leads. In such cases it's important to collagen, gelatin or a similar protein or one Add composition to ensure the correct consistency.

At the Most preferably, the deactivated bone material becomes selective deactivated bone material as described in the co-pending application USSN 08 / 873,276, filed June 11, 1997, or from the University of Florida Tissue Bank, Inc. (UFTB), 1 Innovation Drive, Alachua, Florida 32615, 904-462-3097 or 1-800-OAGRAFT, available is. This material has been treated to be non-collagenous bone proteins to remove what is a non-immunogenic, disease-free, selective deactivated bone product leaves behind. This product has natural chemistry and the mineral, microcrystalline structure of bone with a consistency that is desired Shapes can be brought.

The selectively deactivated product is preferred because it is a microstructure which of all known treated bone products has the natural one Bones closest comes. This bone product also has radiopacity of natural Bone and does not show the dense white image of the bone mineral from Spector. The selectively deactivated product ensures Furthermore a superior one Resorbability, especially when combined with an osteogenic factor becomes. It has been shown that the Resorption advantageously takes place within a few months, unlike some years in Spector's material or the few weeks of the produce of Urist. If the material combined with a bone growth factor, is the absorption time adequate to those required for fusion and bone healing bone bridge to build. The selectively deactivated material also has one Elasticity similar to natural Bone while the materials of Spector and Geistlich are brittle and weak have proven.

The deactivated bone materials of this The invention is preferably combined synergistically with an osteogenic composition or a material containing a bone growth factor or protein. An osteogenic material may be applied to the bone material by impregnating the graft with a solution including an osteogenic composition. The composition may be applied by the surgeon during surgery, or the spacer may be provided with the previously applied composition. In such cases, the osteogenic composition may be stabilized for transport and storage, for example by freeze-drying. The stabilized composition can be rehydrated and / or reactivated with a sterile liquid, such as saline or water, or with body fluids applied before or after implantation. The term osteogenic composition as used herein means virtually any material that promotes bone growth or healing, including natural, synthetic, and recombinant proteins, hormones, and the like.

The include osteogenic compositions used in this invention preferably one for stimulating or inducing bone growth or healing therapeutically effective amount of a substantially pure Bone induction factor, such as a bone morphogenesis protein, in one pharmaceutically acceptable carrier. The preferred osteoinductive factors are the recombinant human bone morphogenetic proteins (rhBMP), because they are in unlimited Quantities available are transmitted and no infectious diseases. Most preferred the bone morphogenesis protein is a rhBMP-2, rhBMP-4 or heterodimer the same. The concentration of rhBMP-2 is generally 0.4 mg / ml to 1.5 mg / ml, preferably near 1.5 mg / ml. However, every bone morphogenesis protein becomes provided, including as BMP-1 up to and including BMP-13 designated bone morphogenesis proteins. BMP are available from The Genetics Institute, Inc., Cambridge, Massachusetts, and may as well prepared by professionals in the field, as described in the US patents No. 5,187,076 to Wozney et al., 5,366,875 to Wozney et al., 4,877 864 to Wang et al., 5,108,922 to Wang et al., 5,116,738 to Wang et al., 5,013,649 to Wang et al., 5,106,748 to Wozney et al. and PCT Patent No. WO93 / 00432 to Wozney et al., WO94 / 26893 Celeste et al. and WO94 / 26892 to Celeste et al. is described. All osteoinductive factors are considered, whether won or not above or isolated from bone. Method of isolating bone morphogenesis protein from bone are described in US Pat. No. 4,294,753 to Urist et al., 81st PNAS 371, 1984.

The Choice of carrier material for the osteogenic composition is based on biocompatibility, biodegradability and interfacial properties. The the Bone growth inducing composition may be on any suitable manner be introduced into the pores of the bone material. For example, the composition may be in the pores of the graft be injected. In other embodiments, the composition dripped onto the graft, or the graft will be in a solution that an amount of the composition effective to stimulate osteoinduction contains soaked. In any case, the pores are for a sufficient period of composition exposed to to enable that the liquid the graft completely saturated. The osteogenic factor, preferably a BMP, can be freeze-dried Provided in a pharmaceutically acceptable liquid or gel carrier, like For example, sterile water, physiological saline or any other suitable carrier, to be reconstituted. The carrier can be any suitable medium that is capable of Proteins to the spacer leave. Preferably, the medium becomes known in the art is, with a buffer solution added. In a specific embodiment rhBMP-2 in a carrier, such as water, Saline, liquid Collagen or injectable bicalcium phosphate, suspended or the same mixed. The BMP solution may be dripped into the graft or the graft may be in a suitable amount of the liquid be dipped. In a most preferred embodiment BMP is applied to the pores of the graft and then lyophilized or freeze-dried. Thereafter, the graft BMP composition for Storing and transporting to be frozen.

at a specific embodiment For use in the cervical spine, the body has a Height of 8 mm and a diameter of 11 mm. The sleeve has a total height of 10 mm including the teeth and a height from something over 8 mm between the teeth. In the specific embodiment has the sleeve an inner diameter, slightly smaller than 11 mm, and a wall thickness of about 1 mm. The sleeve will with twenty-four openings, evenly in size and space, provided, which have a diameter of about 2 mm.

The implants and spacers of this invention can be implanted according to surgical techniques that are well known in the art. Additionally, the implants and spacers may subsequently undergo a complete or partial nucleotomy of the instrumented disc be implanted.

implants and spacers according to the present invention have compressive strengths that be sufficient to withstand the normal stresses on the spine. These implants according to the invention and spacers are at least as firm as tricortical iliac crest grafts. The implants and spacers have a compressive strength according to ASTM C-773 of at least 7 MPa, preferably at least 20 MPa and in particular at least 40 MPa Under these loads, the outer sleeve will bend or break carry most of the stress to the more brittle and weaker ceramic material to protect it.

implants The advantages of porous deactivated bone materials according to this invention with stronger materials, such as metals. The implants guarantee immediate load capacity without shielding against load. The sleeve made of the firmer materials exists, guaranteed a tension band around the porous one biocompatible Material to break the body prevent. The body wears the Initial load and transfers it slowly on the newly formed bone. The porous biocompatible deactivated bone material guaranteed a big surface for the Ingrowth of bones and eliminates the need for autograft. The deactivated bone material is finally absorbed and passed through Replaced host bone.

The Use of a deactivated bone body in synergetic connection with a bone growth factor in this invention solves many the problems of bone graft use. The deactivation procedure eliminates immunogenic and pathogenic agents while it The natural Microstructure of the bone receives. this makes possible Advantageously, the use of xenograft that is in practically unlimited amount is available. Enriching the graft with a bone growth factor results in an osteoinductive graft, that the pain and the danger of obtaining an autograft unnecessary power. The connection of a deactivated bone material with a reinforcing element provides a load-bearing graft that has the disadvantages a metal implant, such as shielding against stress avoids. Therefore, this invention combines all the advantages of autograft, Allograft, xenograft and metal spacers without one of the corresponding disadvantages.

While the Invention illustrated in the drawings and the foregoing description and have been described, are the same as illustrative and non-limiting It is self-evident that only the preferred embodiment has been shown and described, and that changes and modifications fall within the scope of the invention as defined in the appended claims.

REFERENCES

The The following references indicate the level of knowledge in the field.

• An et a., Porous Biphasic Ceramics for Cervical Fusion, Spine, for publication accepted, 1995.
• Delecrin et al., Biphasic Calcium Phosphate as a Bone Graft Substitute for Spine Fusion: Stiffness Evaluation, Fourth World Biomaterials Congress, 1992 (p. 644).
• Li Yubaoi et al., The Influence of Multiphase Calcium Phosphates Bioceramics on Bone Formation in Nonosseous Tissues, Society for Biomaterials, 1993 (p. 165).
• Toth et al., Ceramic-induced Osteogenesis Following Subcutaneous Implantation of Calcium Phosphates, Bioceramics, Vol. 6, ed. Ducheyne & Christianson, 1993 (Pp. 9-14).
• Toth et al., Comparison of Compressive Strengths of Iliac Bone Grafts and Porous Calcium Phosphate Ceramics for Spine Fusion, Orthopedic Research Societv, 1994 (p. 719).
• Xingdong et al., Initiation of the Osteoinduction in Calcium Phosphate Ceramics with the Bone Growth Factor, Society for Biomaterials, 1993 (p. 299). U.S. Pat. No. 5,282,861 to Kaplan. US Patent No. 5,417,975 to Lussi et al. U.S. Patent No. 4,314,380 to Miyata et al. U.S. Patent No. 5,573,771 to Geistlich et al. US Patent No. 4 882 149 to Spector,
• A Chemosterilized Antigen-Extracted Autodigested Alloimplant for Bone Banks, by Urist, MD, et al., in Arch Surg / Bd. 110, April 1975th
• Xenogenic Bone Grafting in Humans, by Salama, in Xenogenic Bone grafting, number 174, April 1983.

Claims (28)

Interbody fusion spacer, comprising: a body ( 11 ) with an outer surface ( 13 ) and a height that approximately corresponds to the height of a human disc space, and one with the outer surface ( 13 ) of the body ( 15 ), wherein the sleeve contains a material, relatively stronger under compression than the body, characterized in that the body consists of a deactivated bone material, including collagen or gelatin and naturally associated bone mineral substances, and that the deactivated bone material substantially free of non-collagen Is protein. Interbody fusion spacer according to claim 1, that as well one inside the body dispersed, therapeutic for stimulating bone growth effective amount of bone growth factor. Interbody fusion spacer according to claim 1 or 2, where the natural Bone material contains native collagen materials. Interbody fusion spacer according to one of claims 1 to 3, wherein the sleeve ( 15 ) a plurality of openings ( 16 ) through the same in connection with the outer surface ( 13 ) of the body ( 11 ), for ingrowth of bones. Spacer according to claim 4, in which the openings ( 16 ) are generally circular. Spacer according to claim 4, in which the openings ( 16 ) are generally oval. Spacer according to claim 4, in which the openings ( 16 ) are generally diamond-shaped. Spacer according to claim 4, in which the openings ( 16 ) are generally rectangular. Interbody fusion spacer according to one of the preceding claims, in which the sleeve ( 15 ) an inner surface ( 17 ) for touching the outer surface ( 13 ) of the body ( 11 ), wherein the inner surface of the sleeve defines a chamber, the sleeve is made of a temperature-responsive material, so that the chamber ( 18 ), when the sleeve is in a heated state, has a first inner dimension that is slightly larger than an outer dimension of the body to slidably receive the body therein, and the chamber (FIG. 18 ), when the sleeve is in a cooled state, has a second inner dimension 'that is slightly smaller than the body, thereby clamping the body therein. Interbody fusion spacer according to one of the preceding claims, in which the sleeve ( 15 ) a height less than the height of the outer surface ( 13 ), to allow contact of the opposing surfaces with endplates of the respective vertebrae when the spacer is implanted between the vertebrae. An interbody fusion spacer according to any one of the preceding claims, further comprising a fastener ( 23 ) for securing the sleeve to the end plates of the adjacent vertebral bodies. Spacer according to Claim 11, in which the sleeve ( 15 ) a lower end ( 27 ) and an upper end ( 26 ) and the fastening means arranged on the upper end and the lower end of the sleeve teeth ( 23 ). Spacer according to Claim 11, in which the sleeve ( 15 ) a lower end ( 27 ) and an upper end ( 26 ) and the fastener defines roughened surfaces defined at the top and bottom of the sleeve ( 33 . 34 ). Interbody fusion spacer according to one of the preceding claims, in which the body ( 11 ) is cylindrical and the sleeve ( 15 ) is a hollow cylinder. An interbody fusion spacer according to any one of the preceding claims, wherein the opposing surfaces of the body ( 11 ) each have a size and shape corresponding to the shape of a vertebral end plate. Interbody fusion spacer according to one of the preceding claims, in which the sleeve ( 15 ) has an outer shape that approximately corresponds to the shape of a Wirbelendplatte. Interbody fusion spacer according to one of the preceding claims, in which the sleeve ( 15 ) consists of a metallic material. spacer according to claim 17, wherein the metallic material includes a metal selected from the group consisting of tantalum, niobium, hafnium and tungsten and alloys the same exists. spacer according to claim 17, wherein the metallic material is a tantalum foam is. Spacer according to Claim 17, in which the sleeve ( 15 ) of a metallic material, including a metal selected from the group consisting of titanium, titanium-vanadium-aluminum alloy, cobalt-chromium alloy, cobalt-chromium-molybdenum alloy, cobalt-nickel-chromium-molybdenum alloy Alloy and biocompatible stainless steel. spacer according to claim 20, wherein the biocompatible stainless steel 316 LVM stainless steel is. Spacer according to Claim 17, in which the metal sleeve ( 15 ) Includes titanium. Interbody fusion spacer after a of the preceding claims, where the spacer has a compressive strength according to ASTM C-773 of at least 7.1 MPa. spacer according to claim 23, wherein the spacer has a compressive strength of has at least 20 MPa. spacer according to claim 23, wherein the spacer has a compressive strength of has at least 40 MPa. Interbody fusion spacer according to one of the preceding claims, in which the body ( 11 ) has a kidney-shaped cross-section to conform to the shape of vertebral endplates. Interbody fusion spacer according to one of the preceding claims, in which the body ( 11 ) is configured so that its size and shape approximately correspond to a nucleus pulposus of a natural intervertebral disc. Interbody fusion spacer after a of the preceding claims, where the bone material is bovine bone.